Well perforating apparatus



Aug. 28, 1956 E. N. JONES 2,760,435

WELL PERFORATING APPARATUS Augazs, 1956 E. N. JONES 2,760,435

I WELL PERFORATING APPARATUS F'i1 ed July 12, 1950 2 Shees-Sheet 2 Edward N. Jones INVENToR.

BY aaa/muy HM@ WELL PERFORATIN G APPARATUS Edward N. Jones, Pettus, Tex.

Application Jury 12, 195o, serial No. 173,307

7 Claims. (Cl. 102-2L8) This invention relates to new and useful improvements in blasting apparatus and the primary Object of the present invention is to provide a device for perforating the walls of a well casing.

Another important object of the present invention is to provide a blasting apparatus including a barrel having a plurality of vertically swingable arms mounted thereon for engaging the inner walls of a well casing to support the barrel within the well casing, and a plurality of blasting caps carried by each arm and contacting the inner walls of the casing when the barrel is supported in the casing by the arms.

A further object of the present invention is to provide a blasting apparatus constructed of inexpensive material that may be completely destroyed during the blasting operation without any appreciable cost and thereby reducing to a minimum the amount of costly material lost during blasting.

A still further aim of the present invention is to provide a blasting apparatus that is simple and practical in construction, efcient and reliable in operation, extremely simple to actuate, safe in use, inexpensive to manufacture, and otherwise well adapted for the purposes for which the same is intended.

Other objects and advantages reside in the details of construction and operation as more fully hereinafter described and claimed, reference being had to the accompanying drawings forming part hereof, wherein like numerals refer to like parts throughout, and in which:

Figure 1 is a vertical sectional view of a Well casing and showing the present invention about to be lowered into the casing;

Figure 2 is a vertical sectional view of a well casing and showing the present invention suspended and locked against the inner walls of the well casing;

Figure 3 is an enlarged fragmentary vertical sectional view through the center of the present invention and with dotted lines showing the striker forced downwardly by a striking element;

Figure 4 is a transverse horizontal sectional view taken substantially on the plane of section line 4 4 of Figure 3;

Figure 5 is a transverse horizontal sectional view taken substantially on the plane of section line S-S of Figure 3; and

Figure 6 is a transverse horizontal sectional view taken substantially on the plane of section line 6--6 of Figure 3.

Referring now to the drawings in detail, wherein for the purpose of illustration, there is disclosed a preferred embodiment of the present invention, the numeral 10 represents an elongated barrel or hollow body having a plurality of vertically and circumferentially spaced recesses 12 that receive the inner ends of vertically swingable links 14. The inner ends of the links 14 are held Within recesses 12 by horizontal pins 16 that extend through the walls of the barrel and the inner ends of the links.

A plurality of elongated arms or holding strips 18 parallel the barrel 10 and are received in and pivoted to nited States atent "a 2,760,435 Patented Aug. 28, 1956 the outer bifurcated ends 20 of the links 14 so that the arms may swing vertically relative to the barrel 10. 'I'he arms 18 are provided with a plurality of vertically spaced horizontal apertures in which jet shots or blasting caps 22 are mounted. The outer ends of the caps 22 project laterally from the arms to engage the inner walls of a well casing 24 in which the barrel and the arms are lowered. The caps 22 each contain suicient explosive material to penetrate the walls of the casing 24 and thereby perforate the walls of the casing.

The upper internally threaded end of the barrel 10 receivably engages a retainer ring 26 that connes antifriction elements or balls 28 upon an internal shoulder 30 in the barrel 10. The balls 28 rollingly guide a sliding striker or plunger 32 having a transverse bore 34 in which there is received a shear pin 36 whose ends are supported upon the retainer ring 26.

A transverse slot 3S is provided in the striker 32, above the bore 34, and sldably receives a bail 40 that is terminally attached to the upper end of the barrel 10. The upper end of the barrel 10 is provided with an axial bore 42 that receives a lowering cable 44 whose lower end is attached to the bail 40.

Suitably secured within the lower end of the barrel 10, is a guide sleeve 46 having an internal groove 48 in which anti-friction elements or balls 50 are mounted to ride against the outer periphery of a substantially cylindrical hammer 52.

A support ring 54 is threaded in the lower end of the sleeve 46 and supports a detonating or blasting cap 56 which underlies a second detonating or blasting cap 58 also Within the guide sleeve 46. A firing element 60 is interposed between the bases of the caps 56 and 5S and includes upper and lower pointed ends or apices that contact the central portions of the bases of the caps 56 and 58.

The sleeve 46 constitutes the blasting chamber and its lower end communicates with a recess 60 in the upper end of a nose member 62 that is detachably secured to the lower end of the barrel 10. Transverse recesses 64 in the nose member 62 receive packing glands 66 through which a detonating cord or prima cord 68 is extended. The cord 68 extends through the recess 60 to be detonated by the cap 56 and the cord 68 is connected to at least the lower caps of the arms.

The caps or charges 22 are located suificiently close together so that when the charges connected to the cord 68 are set olf, all of the charges 22 will be sympathetically discharged to effectively perforate the walls of the casing 24.

ln practical use of the present invention, the apparatus is lowered into the casing 24 by the cable 44 whereupon an upward pull on the cord or cable 44 will force the arms 18 and the caps 22 against the inner walls of the casing 24 to support the barrel as shown in Figure 2.

A striking element 7l) is then forced downwardly against the striker 32, to shear the pin 36 and cause the striker 32 to force the hammer against the upper cap 5S and the cap 58 against the upper apex of the member 6@ and the lower apex of the member 60 against the lower cap 56, whereupon both caps 56 and 5S will be detonated thereby detonating the cord 63 and the caps or charges 22.

in view of the foregoing description taken in conjunction with the accompanying drawings it is believed that a clear understanding of the device will be quite apparent to those skilled in this art. A more detailed description is accordingly deemed unnecessary.

it is to be understood, however, that even though there is herein shown and described a preferred embodiment of the invention the same is susceptible to certain changes fully comprehended by the spirit of the invention as herein described and the scope of the appended claims.

Having described the invention, what is claimed as new is: v

-l. In a perforating gun for oil wells, an elongated barrel provided with a central bore, explosive charges arranged and supported on the outside of said barrel and spaced therefrom in operative position, said barrel being provided with a nose containing a cavity and bores leading from said cavity to the outside, a prima cord extended within said cavity passing through the last named bores to the outside connected with explosive charges carried on the outside of the barrel, an impact responsi 'e plunger held within said central bore of the barrel adapted to be displaced longitudinally within said barrel upon impact of a striking element, a detonator including a firing pin tixedly held within said barrel in the vicinity of the cavity, a communication channel between said detonator and said cavity and a movable element exposed to the impact responsive plunger between the latter and the detonator, the plunger upon impact driving the tiring pin into the detonator and detonating the prima cord which hres the explosive charges.

2. ln a perforating gun for oil wells an elongated barrel provided with a central bore, explosive charges arranged and supported on the outside of said barrel and spaced therefrom when in operative position, said barrel being provided with a nose containing a cavity and with bores leading from said cavity to the outside, a prima cord held within said cavity extending to the outside by passing through the last named bores, a sleeve element held xedly within the central bore of the barrel near the cavity and the nose of the barrel, said sleeve element having a central channel, communicating with said cavity, a detonator held near the end of said central channel, a tiring pin in contact with said detonator, a longitudinally movable element in said central channel of the sleeve element adapted to press on the tiring pin, said longitudinally movable element being exposed to the impact of the impact responsive plunger, the plunger upon impact driving the movable element towards the tiring pin and the latter driving the tiring pin into said detonator and detonating the prima cord which lires the explosive charges.

3. ln a perforating gun for oil wells an elongated barrel provided with a central bore, an explosive charge carrier arranged in substantial parallelism with the barrel, said carrier carrying a plurality of explosive charges, means for suspending the explosive charge carrier movably on said barrel, said barrel -being provided with a nose containing a cavity and bores leading from said cavity to the outside, a prima cord held within said cavity and extending to the outside through the last named bores, said prima cord being connected with explosive charges on said charge carrier, an impact responsive plunger held within said central bore of the barrel .adapted to be displaced longitudinally within said barrel upon impact of a striking element, a detonator including a firing pin, tixedly held within said barrel in the vicinity of the cavity in the nose of the barrel, a communication channel between said detonator and said cavity and a movable element exposed to the impact responsive plunger between the latter and the detonator, the plunger upon impact driving the tiring pin into the detonator and detonating the prima cord which fires the charges.

4. ln a perforating gun for oil wells provided with a Well casing, an elongated barrel provided with a central bore, a plurality of elongated arms forming explosive charge carriers arranged in substantial parallelism with the barrel, each of said arms carrying a plurality of explosive charges, means for suspending the said explosive charge carrier arms movably on said barrel and for spacing the said arms from the barrel at different distances from the barrel to apply them against the well casing, said last named means holding the said explosive charge carrier arms always in a position parallel to the barrel, with the explosive charges arranged one below the other, said barrel being provided with'a nose containing a cavity and bores leading from said cavity to the outside, a prima cord extending through said cavity and to the outside passing through said last named bores, said prima cord being pliable and extensible-and permanently connected with the explosive charges at the lower end of the arms, an impact responsive plunger held within said central bore of the barrels adapted to be displaced longitudinally within said barrel upon impact of a striking element, a detonator including a tiring pin, said detonator being ixedly heid within said barrel in the vicinity of the cavity in the nose of the barrel, a communication channel between said detonator and said cavity and a movable element exposed to the impact responsive plunger between the latter and the detonator, the plunger upon impact driving the tiring pin into the detonator and detonating the prima cord which lires the explosive charges.

5. In a perforating gun for perforating oil well casings an elongated barrel provided with a central bore, carrying on the outside a plurality of explosive charges, an impact responsive detonating means within said barrel including an actuator disposed on the inside of the barrel and extending to an explosive charge on the outside, a tripping assembly carried by said barrel including an impact responsive plunger adapted to slide within said central bore of the barrel for detonating the impact responsive detonator, said impact responsive plunger being provided with a portion projecting upwardly beyond the upper end of the barrel and having at its end a striker plate, said upwardly projecting portion being provided with a central bore and with elongated axially extending slots at diametrically opposite sides, means rupturable upon an impact on the plunger exceeding a predetermined limit for holding said plunger within said barrel, a ilexible suspension means for said barrel extending through the central bore of the plunger projection and attached to the barrel below the end of the plunger projection by a bail attached to the barrel and passing through the axial slots of the upwardly projecting portion of the plunger, the striker plate being thus exposed to and receiving an impact from a striking element dropped into the oil Well casing which is automatically guided towards the striker and detonates the impact responsive detonator inside the barrel, the detonator detonating the actuator disposed on the inside of the barrel and extending to the outside which in its turn detonates the explosive charges on the outside.

6. In a perforating gun for perforating oil well casings an elongated barrel with a central bore, carrying on the outside a plurality of explosive charges spaced from said barrel, an impact responsive detonating means for exploding said charges, disposed within said barrel and including an actuator extending to the outside, an impact responsive plunger Within said barrel for detonating said impact responsive detonating means, and a tripping assembly carriedby said barrel, said impact responsive plunger having a portionV projecting beyond the barrel which is provided with a central bore and with axially disposed slots at opposite sides, said plunger being held within said barrel by a breakable means ruptured upon impact, said plunger causing the detonation of the detonating means upon impact, the tripping assembly including a flexible suspension element attached to said barrel below the upper end of the plunger projection by means of a bail attached to the upper end of said barrel, said bail extending through the axial slots of the projection of said plunger, the exible suspension element extending through the central bore of the last named projection, a striker plate on the top of said projection of the plunger, said flexible element forming a guide for a striking element moving towards said striking plate. Y

7. In a perforating gun for perforating oil well casings, an elongated barrel adapted for longitudinal insertion into a well casing, a pair of arms each pivotally linked to the barrel by parallel pvoted levers, so as to maintain the arms permanently in a position parallel to the barrel, said arms being moved outwardly from the barrel upon upward movement of the barrel to engage the inner Wall of the well casing, explosive charges longitudinally spaced along each of said arms, detonating means within the cavity of said barrel for detonating said explosive charges, the detonating means including an explosive charge Within said barrel and a detonating cord, activated by an explosive charge Within the barrel, with flexible portions extending to the outside and connected with said explosive charges on each arm, detonation of one of said explosive charges on the arms serially detonating the remaining charges sympathetically to provide longitudinally spaced perforations in the well casing.

References Cited in the iile of this patent UNITED STATES PATENTS 1,526,274 Fitzsimons et al. Feb. 10, 1925 1,875,583 Fox Sept. 6, 1932 2,120,464 Hall June 14, 1938 2,210,125 Raymond Aug. 6, 1940 2,254,979 Ricou Sept. 2, 1941 2,399,211 Davis et al. Apr. 30, 1946 2,616,370 Foster Nov. 4, 1952 

1. IN A PERFORATING GUN FOR OIL WELLS, AN ELONGATED BARREL PROVIDED WITH A CENTRAL BORE, EXPLOSIVE CHARGES ARRANGED AND SUPPORTED ON THE OUTSIDE OF SAID BARREL AND SPACED THEREFROM IN OPERATIVE POSITION, SAID BARREL BEING PROVIDED WITH A NOSE CONTAINING A CAVITY AND BORES LEADING FROM SAID CAVITY TO THE OUTSIDE, A PRIMA CORD EXTENDED WITHIN SAID CAVITY PASSING THROUGH THE LAST NAMED BORES TO THE OUTSIDE CONNECTED WITH EXPLOSIVE CHARGES CARRIED ON THE OUTSIDE OF THE BARREL, AN IMPACT RESPONSIVE PLUNGER HELD WITHIN SAID CENTRAL BORE OF THE BARREL ADAPTED TO BE DISPLACED LONGITUDINALLY WITHIN SAID BARREL UPON IMPACT OF A STRIKING ELEMENT, A DETONATOR INCLUDING A FIRING PIN FIXEDLY HELD WITHIN SAID BARREL IN THE VICINITY OF THE CAVITY, A COMMUNICATION CHANNEL BETWEEN SAID DETONATOR AND SAID CAVITY AND A MOVABLE ELEMENT EXPOSED TO THE IMPACT RESPONSIVE PLUNGER BETWEEN THE LATTER AND THE DETONATOR, THE PLUNGER UPON IMPACT DRIVING THE FIRING PIN INTO THE DETONATOR AND DETONATING THE PRIMA CORD WHICH FIRES THE EXPLOSIVE CHARGES. 